Floyd County covers 992 square miles. The mostly flat land is broken on the east by the Caprock and Rolling Plains and on the south by the White River and Blanco Canyon. The elevation ranges from 2,600 to 3,300 feet. The northeast corner has level to undulating soils, with some clayey subsoils. The remainder of the county has nearly flat terrain and alkaline soils with dark loamy surfaces and clayey subsoils. Vegetation is typical of the High Plains, with moderately short to tall grasses and plenty of mesquiteqv. Between 71 and 80 percent of the land in the county is considered prime farmland; about 500,000 acres is considered arable.

The climate is arid and mild, with cool winters and hot summers. Temperatures range in January from an average low of 24° to an average high of 53°, and in July from 67° to 94°. The average annual rainfall is nineteen inches, and the average relative humidity is 73 percent at 6 A.M. and 39 percent at 6 P.M. The average annual snowfall is eleven inches. The growing season averages 213 days per year, with the last freeze in early April and the first freeze in early November.

Evidence of prehistoric hunters has been found in Floyd County, which was part of the vast domain of the Plains Apaches and later of the Comanches. Spanish explorer Francisco Vázquez de Coronado is believed to have come through the area in 1541. Quitaque Peak was a familiar landmark to José P. Tafoya and other Comancheros who came from New Mexico to trade with the warlike "Mongols of the West"; indeed, it marked the southern boundary of the notorious Valley of Tears, so named because white captives were separated among various Indian bands or ransomed there by Comancheros. In August 1841 the Texan-Santa Fe expeditionqv members established Camp Resolution near the junction of Quitaque and Los Lingos creeks, in the county's northeastern part, and there made the fateful decision to split into two groups in a desperate bid to reach their objective.

In 1871 and again in 1874 Col. Ranald S. Mackenzie's Fourth United States Cavalry came through Floyd County in pursuit of the hostile Quahadi Comanches. In their wake came hide hunters operating out of Fort Griffin and Charles Rath's Teepee City. With the Indians and buffalo gone, ranchers entered the area with their free-range cattle outfits. The Baker brothers and O. J. Wiren established the headquarters of the Quitaque (Lazy F) Ranchqv, later owned by Charles Goodnight and for a time part of the JA Ranch, on the banks of Quitaque Creek. The firm of Owens, Marseilles and Duncan grazed both cattle and sheep on its H Bar L (later the TM Bar) Ranch in Blanco Canyon. Other pioneer ranches that had land in Floyd County included the Two-Buckle and the Matador.

On August 21, 1876, the Texas legislature formed Floyd County, named for the Alamo martyr Dolphin Ward Floyd, as one of the fifty-four counties established from the Bexar and Young territories. In 1884 Arthur B. Duncan and his family became the county's first settlers when they located in Blanco Canyon a short distance above Henry Clay (Hank) Smithqv's ranch in Crosby County. Since Floyd County at that time was attached to Donley County for administrative purposes, the Duncans and other settlers who soon followed had to go to Clarendon to file on state lands for homes. In the spring of 1887, Thomas J. Braidfoot and his family located on a section of school land that afterward was platted as the town of Della Plain. There the county's first school was begun late in 1888.

The move to organize Floyd County produced heated rivalry among its developing communities for the honor of being the county seat. Lockney, which became Della Plain's chief rival, was founded in 1889. In the spring of 1890 J. K. Gwynn appeared on the scene as a representative of Carolina V. Price, a Missouri native who owned numerous patented sections in Floyd County. Gwynn had one of the prize sections platted as Floyd City, another candidate for county seat. Lockney combined with Floyd City, and in the organization election on May 28, 1890, Floyd City won by a vote of 55 to 33. The election was subsequently contested in the district court and later in the Supreme Court, but its validity wassustained; Floyd City, renamed Floydada in 1892, remained the seat of local government, with A. B. Duncan serving as the first county judge.

Although Floyd County had a population of 529 by 1890, droughts, financial panics, and grasshopper plagues caused many settlers to vacate the region during the next decade. Some of the communities, including Della Plain and Mayshaw, were abandoned, but Lockney was revived in 1894 with the establishment of Lockney Christian College, which lasted until 1917. A gradual influx of population resulted in a movement to choose a new county seat and build a new courthouse, but in the election of 1912 Floydada was again victorious by a small majority. After that, town and sectional rivalries waned.

The first railroad to build into the county was the Santa Fe, which in 1910 built a branch line from Plainview to Lockney and Floydada. In 1928 the Quanah, Acme and Pacific Railway extended its tracks from McBain, thus connecting Floydada directly with points east and north. At the same time, the Fort Worth and Denver constructed its South Plains line from Estelline and Quitaque to Lockney via Sterley and South Plains. This line, later taken over by Burlington Northern, is noted for the Quitaque Tunnel, a remarkable engineering feat that is now the state's only functioning railway tunnel, located in northeastern Floyd County.

The construction of the railroads brought numerous new settlers to the area. Between 1900 and 1930 the population increased six-fold, growing from 2,020 to 12,409. Many of the new settlers were farmers, lured to the area by abundant land, and during the first three decades of the twentieth century the number of farms in the county grew rapidly. In 1900 there were only 286; by 1930 that figure had grown to 1,671. Corn was the most important crop in the early years, but after 1900 wheat and cotton were both introduced on a commercial scale. By 1930 Floyd County farmers were harvesting more than two million bushels of wheat annually, making the county one of the leaders in the state in wheat culture. Cotton culture also saw impressive growth, particularly after 1920. By 1930 nearly one-fifth of the improved land in the county-71,184 of 490,731 acres-was devoted to cotton. Production increased from 430 bales in 1910 to 42,801 bales in 1926, one of the peak years of the cotton boom.

The 1920s and 1930s saw other important improvements. Tractors began to be used on a large scale, and numerous new roads were laid out and graded. In 1937 paved highways came to Floyd County with the completion of State Highway 28 (now U.S. 70) through Floydada.

During the early 1930s cotton was the leading cash crop. Falling prices, droughts, and boll weevil infestations, however, combined to drive down cotton production in the 1930s. Although the amount of land planted in cotton continued to be quite high, both yields and profits dropped significantly, especially after 1932. In 1936 Floyd County farmers produced only 11,137 bales, only slightly more than a quarter of the peak figure for the mid-1920s.

Because of the rapidly growing population, land prices showed a marked increase during the second and third decade of the twentieth century, and many new farmers found land impossible to buy. The number of tenants and share croppers grew rapidly, particularly in the 1920s, and by 1930 more than half of county farmers-923 of 1,691-were working someone else's land. In contrast to those in many other areas of the state, the overwhelming majority of the tenants were white. The high rate of tenancy had serious results during the Great Depression of the 1930s. As a result of the poor yields and the reluctance of banks to extend credit to financially strained farmers, many of those who made a living from the land, particularly tenants, found themselves displaced. Numerous farmers were forced to give up their livelihoods and seek work elsewhere. The population of the county as a whole fell from 12,409 in 1930 to 10,659 in 1940.

During the late 1940s agricultural prices began to rebound, but the farming economy did not fully recover until after World War II. Oil, discovered in the county in 1952, helped some cash-strapped farmers to settle long-standing debts, but oil production in Floyd County has been modest compared with that of other counties in the region; between 1952 and 1990 only 123,510 barrels were produced, with an annual production in the late 1980s of around 3,000 barrels.

Since World War II Floyd County has remained a leader in agricultural production. In the years after the war, wheat production continued to grow and cotton made a strong recovery. In 1950 Floyd County farmers grew 2,758,000 bushels of wheat, and 47,332 bales of cotton. Alfalfa, corn, popcorn, and sorghum were also raised in large quantities. Large-scale irrigation was introduced after the war, and by the early 1950s some 150,000 acres were irrigated. Subsequently, agricultural production continued to grow. In the early 1990s more than 220,000 acres was under irrigation and the county's farmers were earning an average $75 million a year. Most of the receipts came from cotton, wheat, vegetables, soybeans, corn, sunflowers, beef cattle, and hogs. Floyd County remained a leading cotton-producing area; twenty-one cotton gins operated in the county in 1990. Additional sources of income included the production of farm machinery and race cars, meat and vegetable processing, and other agribusinesses. Floydada is the site of the Texas A&M Engineering Extension Service. In 1982, 98 percent of the land in the county was in farms and ranches, with 70 percent of the land under cultivation and 59 percent irrigated. Floyd County ranked twenty-first in the state in agricultural receipts, with 75 percent coming from crops. Primary crops were soybeans, sunflowers, cotton, wheat, sorghum, and corn; onions, bell peppers, cucumbers, and pecans were also grown in sizable quantities. The leading livestock products were cattle, milk, and hogs.

The total number of businesses in the county in the early 1980s was 189. In 1980, 24 percent of the labor force was self-employed, 19 percent was employed in professional or related services, 6 percent in manufacturing, 19 percent in wholesale and retail trade, 34 percent in agriculture, forestry, fishing, and mining, and 9 percent in other counties; 894 retired workers lived in the county. Nonfarm earnings in 1981 totaled $68,652,000.

In the early 1980s Floyd County had four school districts, with five elementary, two middle, and two high schools. The average daily attendance in 1981–82 was 2,057, with expenditures per pupil of $2,494. Twenty-two percent of the 127 high school graduates planned to attend college. In 1983, 41 percent of the school graduates were white, 55 percent Hispanic, 5 percent black, and 0.3 percent Asian.

The first churches in Floyd County were established shortly after the organization of the county. In the mid-1980s the county had twenty-eight organized churches, with a estimated combined membership of 8,997. The largest denominations were Baptist, Catholic, and United Methodist. Historically Floyd County has been staunchly Democratic, although Republicans made strong inroads after 1960, particularly in presidential elections and some statewide races. Between 1960 and 1988 Republican presidential candidates received the majority of votes in every race except for Lyndon B. Johnson in 1968 and Jimmy Carter in 1976. Democratic officials, however, continued to maintain control of most county offices.

The population of Floyd County grew between 1950 and 1960 from 10,535 to 12,369, but afterward fell steadily as residents gradually moved away to find jobs. The population was 11,044 in 1970, 9,834 in 1980, and 8,497 in 1990. In 1990, nearly half of the population lived in Floydada (4,193). Other communities included Lockney, Aiken, Barwise, Cedar Hill, Dougherty, Lakeview, Lone Star, McCoy, Mickey, Muncy, Sandhill, South Plains, and Sterley. In 1990, 65 percent of the population was white, 3.8 percent black, 39.8 percent Hispanic, and 0.2 percent Asian. The largest ancestry groups are English, Hispanic, and Irish.

The area is popular with hunters and fishermen, particularly in the fall and winter. The Old Settlers Day Reunion held in Floydada and the Floyd County Fair in Lockney are among the main tourist attractions.